The present invention relates to an electric remote control rearview mirror assembly particularly suited for use in an automobile vehicle.
U.S. Pat. No. 3,609,014, patented on Sept, 28, 1971, discloses an electric remote control rearview mirror assembly for an automobile. This rearview mirror assembly comprises a mirror having a reflective surface and a backside and supported by a mirror support plate with the backside facing the support plate; a spherical mounting member upon which the support plate carrying the mirror is clamped for pivotal movement around horizontal and vertical axes; a support member carrying the spherical mounting member; a pair of ball sockets provided in the support plate in spaced relation to the spherical mounting member and spaced 90.degree. from each other with respect to the spherical mounting member; a pair of externally threaded rods projecting from the support plate, each of the rods having one end pivotally secured in one of the ball sockets against rotational and axial displacement relative to the support plate; a pair of externally threaded nut members rotatably supported by the support member, each of the nut members engaging one of the externally threaded rods; and electric drive means for selectively rotating the nut members to pivotally adjust the support plate about the spherical mounting member to angularly adjust the position of the mirror with respect to the horizontal and vertical axes.
The drive means is described as comprised of either a single electric reversible motor having its drive shaft adapted to be selectively shiftable into and out of driving engagement with either of the nut members by the utilization of a solenoid unit, or two separate electric reversible motors having their drive shafts drivingly engaged to the associated nut members.
Each of the nut members is described as having either an internally threaded bore or an internally smooth bore. Where the nut members have respective internally threaded bores, they are threadingly mounted on the associated rods. However, where the nut members have respective smooth bores, a generally U-shaped spring element is employed for each nut member, one of the opposed arm portions of the U-shaped spring element extending across the smooth bore and passing through a groove between every adjacent two convolutions of the respective external threads on the rod.
In the prior art mirror assembly of the construction described above, it has been found that the manufacture thereof is generally complicated and time-consuming. More specifically, it has often been required, particularly prior to the mirror assembly being packaged for shipment, to effect an manual adjustment of the mirror relative to a mirror box so that the mirrors of the individual remote control rearview mirrors being manufactured can assume substantially the same position relative to the associated mirror boxes. However, the prior art mirror assembly referred to above requires the supply of an electric power to the motor or motors in order to achieve the adjustment of the mirror box relative to the mirror to finish the make-up of the remote control rearview mirror assembly. This involves such a disadvantage that, each time the mirror assemblies being manufactured are successively delivered into the hands of an attendant worker or workers assigned to effect the adjustment of the mirror relative to the mirror box, they have to connect and disconnect the motor or motors to an electric circuit including the electric power source.
However, where the prior art remote control rearview mirror assembly utilizes the generally U-shaped spring elements in conjunction with the nut members having smooth bores, the manual adjustment of the mirror relative to the mirror box may be possible by applying an external pushing force to the mirror so that the individual externally threaded rods can be moved axially permitting one of the opposed arm portions of the U-shaped spring elements to hop from one groove to another under the influence of resiliency of the spring elements. In this case, not only is a relatively large external pushing force required, but also the hopping of that arm portion of the spring elements from one groove to another generates vibrations and noises, and, accordingly, the attendant worker or workers are placed in working conditions uncomfortable to them.